Contractual Obligations, Commercial Commitments and Contingencies (Narrative) (Details) $ in Millions	Dec. 31, 2025 USD ($)
Utility [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Business Combination, Indemnification Asset, Acquisition Date, Amount	$ 60.8
Debt Obligation on 4.9% Equity Ownership [Member] | THE DAYTON POWER AND LIGHT COMPANY [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Equity ownership interest	4.90%
Equity ownership interest aggregate cost	$ 42.8
Electric Generation Company [Member] | THE DAYTON POWER AND LIGHT COMPANY [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Debt obligation	$ 872.8